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This study aimed to develop a new symmetric-end antimicrobial peptide (AMP) with cell selectivity, antibiofilm, and anti-inflammatory activities. Two symmetric-end AMPs, Lf6-pP and Lf6-GG, were designed based on the sequence RRWQWRzzRWQWRR, which contains two symmetric repeat sequences connected by a ß-turn-promoting sequence (zz) that can be a rigid turn by D-Pro-Pro (pP) or a flexible turn by Gly-Gly (GG). Both Lf6-pP and Lf6-GG exhibited potent antibacterial activity without causing hemolysis, but Lf6-pP exhibited better cell selectivity, likely due to the more significant impact of the rigid pP turn. Compared to Lf6-GG, Lf6-pP demonstrated approximately three times higher antimicrobial activity against drug-resistant bacteria, had a low incidence of drug resistance, and maintained its activity in the presence of physiological salts and human serum. Additionally, Lf6-pP was more effective than Lf6-GG in inhibiting biofilm formation and eradicating mature biofilms. The BODIPY-cadaverine assay indicated that the potent anti-inflammatory activity of Lf6-pP may be attributed to its direct interaction with LPS, resulting in decreased TNF-α and IL-6 levels in LPS-stimulated macrophages. Mechanistic studies, including membrane depolarization, outer/inner membrane permeation, and membrane integrity change, demonstrated that Lf6-pP exerts its antibacterial action through an intracellular-target mechanism. Overall, we propose that Lf6-pP has potential as a novel antibacterial, antibiofilm, and anti-inflammatory agent against drug-resistant bacterial infections.
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Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Humanos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Lipopolissacarídeos/farmacologia , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Biofilmes , Testes de Sensibilidade MicrobianaRESUMO
Proadrenomedullin N-terminal 20 peptide (PAMP) is a regulatory peptide that is found in various cell types. It is involved in many biological activities and is rich in basic and hydrophobic amino acids, a common feature of antimicrobial peptides (AMPs). In this study, the cell selectivity and antimicrobial mechanism of PAMP and its C-terminal peptide, PAMP(9-20), were investigated. PAMP and PAMP(9-20) displayed potent antimicrobial activity (minimum inhibitory concentration: 4-32 µM) against standard bacterial strains, but showed no hemolytic activity even at the highest tested concentration of 256 µM. PAMP(9-20) showed 2- to 4-fold increase in antimicrobial activity against gram-negative bacteria compared to PAMP. Cytoplasmic membrane depolarization, leakage of calcein dye from membrane mimic liposomes, SYTOX Green uptake, membrane permeabilization, and flow cytometry studies indicated that the major target of PAMP and PAMP(9-20) is not the microbial cell membrane. Interestingly, laser-scanning confocal microscopy demonstrated that FITC-labeled PAMP and PAMP(9-20) enter the cytoplasm of Escherichia coli similar to buforin-2, and gel retardation assay indicated that PAMP and PAMP(9-20) effectively bind to bacterial DNA. These results suggest that the intracellular target mechanism is responsible for the antimicrobial action of PAMP and PAMP(9-20). Collectively, PAMP and PAMP(9-20) could be considered promising candidates for the development of new antimicrobial agents.
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Adrenomedulina/farmacologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Precursores de Proteínas/farmacologia , Adrenomedulina/química , Animais , Antibacterianos/química , Bactérias/metabolismo , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Membrana Externa Bacteriana/efeitos dos fármacos , Membrana Externa Bacteriana/metabolismo , DNA Bacteriano/metabolismo , Hemólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fragmentos de Peptídeos/química , Precursores de Proteínas/química , OvinosRESUMO
TZP4 is a triazine-based amphipathic polymer designed to mimic the amphipathic structure found in antimicrobial peptides. TZP4 showed potent antimicrobial activity comparable to melittin against antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus and multidrug-resistant Pseudomonas aeruginosa. TZP4 showed high resistance to proteolytic degradation and low tendency to develop drug resistance. The results from membrane depolarization, SYTOX Green uptake, flow cytometry, and gel retardation revealed that the mechanism of antimicrobial action of TZP4 involved an intracellular target rather than the bacterial cell membrane. Furthermore, TZP4 suppressed the messenger RNA levels of inducible nitric oxide synthase and tumor necrosis factor-α (TNF-α) and inhibited the release of nitric oxide and TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. BODIPY-TR-cadaverine displacement and dissociation of fluorescein isothiocyanate (FITC)-labeled LPS assays revealed that TZP4 strongly bound to LPS and disaggregated the LPS oligomers. Flow cytometric analysis demonstrated that TZP4 inhibits the binding of FITC-conjugated LPS to RAW264.7 cells. These observations indicate that TZP4 may exert its antiendotoxic activity by directly binding with LPS and inhibiting the interaction between LPS and CD14+ cells. Collectively, TZP4 is a promising drug candidate for the treatment of endotoxic shock and sepsis caused by Gram-negative bacterial infections.
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Anti-Infecciosos , Peptídeos Antimicrobianos , Polímeros , Triazinas , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana , Endotoxinas/antagonistas & inibidores , Lipopolissacarídeos/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Polímeros/química , Polímeros/farmacologia , Polímeros/toxicidade , Células RAW 264.7 , Triazinas/química , Triazinas/farmacologia , Triazinas/toxicidadeRESUMO
BACKGROUND: Eyelids are important structures and play a role in protecting the globe from trauma, brightness, in maintaining the integrity of tear films and moving the tears towards the lacrimal drainage system and contribute to aesthetic appearance of the face. Ophthalmic trauma is an important cause of morbidity among individuals and has also been responsible for additional cost of healthcare. Periocular trauma involving eyelids and adjacent structures has been found to have increased recently probably due to increased pace of life and increased dependence on machinery. A comprehensive classification of periocular trauma would help in stratifying these injuries as well as study outcomes. MATERIAL AND METHODS: This study was carried out at our institute from June 2015 to Dec 2015. We searched multiple English language databases for existing classification systems for periocular trauma. We designed a system of classification of periocular soft tissue injuries based on clinico-anatomical presentations. This classification was applied prospectively to patients presenting with periocular soft tissue injuries to our department. RESULTS: A comprehensive classification scheme was designed consisting of five types of periocular injuries. A total of 38 eyelid injuries in 34 patients were evaluated in this study. According to the System for Peri-Ocular Trauma (SPOT) classification, Type V injuries were most common. SPOT Type II injuries were more common isolated injuries among all zones. DISCUSSION: Classification systems are necessary in order to provide a framework in which to scientifically study the etiology, pathogenesis, and treatment of diseases in an orderly fashion. The SPOT classification has taken into account the periocular soft tissue injuries i.e., upper eyelid, lower eyelid, medial and lateral canthus injuries., based on observed clinico-anatomical patterns of eyelid injuries. CONCLUSION: The SPOT classification seems to be a reliable system to address eyelid injuries. This classification scheme would guide the ophthalmic and facial reconstructive surgeons to provide optimal outcomes in eyelid injuries. Based on the classification scheme and review of existing literature, an algorithm is presented to facilitate repair and reconstruction.
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The present experiments were studied on bioremediation of denim industry wastewater by using polyurethane foam (PU foam) immobilized bacterial cells. About 30 indigenous adapted bacterial strains were isolated from denim textile effluent out of which only four isolates were found to be efficient against crude indigo carmine degradation using broth decolorization method. The selected bacterial strains were identified as Actinomyces sp., (PK07), Pseudomonas sp., (PK18), Stenotrophomonas sp., (PK23) and Staphylococcus sp., (PK28) based on microscopic and biochemical characteristics. The bacterial immobilized cells have the highest number of viable cells (PK07, PK18, PK23 and PK28 appeared to be 1 x 10(8), 1 x 10(9), 1 x 10(6) and 1 x 10(7) CFU/ml respectively) and maximum attachment efficiency of 92% on PU foam. The complete degradation using a consortium of PU foam immobilized cells was achieved at pH 6, 27 degrees C, 100% of substrate concentration and allowed to develop biofilm for one day (1.5% W/V). In SEM analysis, it was found that immobilization of bacterial cells using PUF stably maintained the production of various extracellular enzymes at levels higher than achieved with suspended forms. Finally, isatin and anthranilic acid were found to be degradation products by NMR and TLC. The decolorized dye was not toxic to monkey kidney cell (HBL 100) at a concentration of 50 µl and 95% of cell viability was retained. A mathematical model that describes bacterial transport with biodegradation involves a set of coupled reaction equations with non-standard numerical approach based on the time step scheme.
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Reatores Biológicos , Corantes/química , Resíduos Industriais/análise , Indústria Têxtil , Eliminação de Resíduos Líquidos/métodos , Adsorção , Corantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Índigo Carmim/química , Índigo Carmim/metabolismo , Cinética , Temperatura , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismoRESUMO
Camphor is a waxy white sublimating chemical derived from natural as well as synthetic sources and widely used in various communities worldwide for a number of medicinal, culinary, and religious reasons. Camphor is burnt as an offering to God in many religious communities. We report three incidences of self inflicted injury from burning camphor on the palm resulting in full thickness burns. Non-suicidal self-injury is socially unacceptable destruction or alteration of body tissue when there is no suicidal intent or pervasive developmental disorder and we have explored an association between this and burn injury. This report also highlights the unique social and cultural pattern of this burn injury and the importance of psycho-therapeautic help for these victims.
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Introduction Breast lumps in any age group are addressed cautiously to exclude the possibility of breast cancer. The clinical approach to breast lumps involves the "triple test" for cancer screening. The triple test includes clinical examination, imaging (mammogram or ultrasonogram), and tissue sampling (fine needle aspiration cytology (FNAC) and core needle biopsy). These tests happen in a sequential process, and it is important that their findings support the final diagnosis for accurate management of the patient. Aims and objectives This study aims to determine the correlation between the histopathological and radiological findings among the various breast lesions and describe the spectrum of breast lesions received in our center. Methods This is a retrospective observational study for a period of three years, from January 2020 to December 2022. The study included 400 patients who had undergone ultrasonography or mammograms for breast lumps, FNAC, core needle biopsy, or surgical resection. The data collected was analyzed for concordance and discordance status. Results A total of 400 cases were reviewed. There were 238 (59.5%) histologically confirmed benign breast lesions and 162 (40.5%) malignant lesions with their corresponding BI-RADS (Breast Imaging Reporting and Data System) scores. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for the imaging modalities (ultrasonogram and mammogram) in diagnosing breast lesions were 95.06%, 94.96%, 92.77%, 96.58%, and 95%, respectively, which were comparable with other similar studies. The biological and immunohistochemical factors of all the invasive carcinomas were studied in detail. Conclusions Imaging modalities (ultrasonogram or mammogram) have good sensitivity and specificity in diagnosing breast lesions and can be reliably used as a preliminary test in breast lump evaluation. The BI-RADS score is a reliable indicator and can be considered for the effective follow-up or intervention of the breast lesion. In discordant cases, a repeated core needle biopsy or excision has to be recommended, as pathological diagnosis is the cornerstone of effective management. A good rapport between the surgeon, radiologist, and pathologist aids in effective feedback and learning for achieving diagnostic accuracy.
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The aim of this study was to assess the open pond and groundwater quality of Tiruchirapalli city of Tamil Nadu, India. The groundwater quality viz., pH, electrical conductivity, total hardness, calcium ion, magnesium ion, chloride, carbonate, bicarbonate, inorganic nitrate, nitrite, phosphate, ammonia and reactive silicate were analysed with respect to various seasons and recorded in the range of 7.1 to 8.1, 97.67 to 533.67 mhos cm(-1), 7.07 to 186 mg l(-1), 4.67 and 112.0 mg l(-1), 2.40 to 92.80 mg l(-1), 15.23 to 661.73 mg l(-1), 60 to 480 mg l(-1), 22.7 to 544.9 mg l(-1), 15.33 to 68.00 mg l(-1), 0.001 to 0.480 mg l(-1), 0.01 to 0.42 mg l(-1), 0.02 to 0.75 mg l(-1) and 1.1 to 2.96 mg l(-1) respectively. The present findings concluded that the quality of ground waters can be considered suitable for human consumption. But the pond water available in and around Tiruchirappalli city was not fit for human usage, agricultural or industrial purposes.
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Água Subterrânea/química , Lagoas , Estações do Ano , ÍndiaRESUMO
OBJECTIVES: We recently designed a series of cationic deoxythymidine-based amphiphiles that mimic the cationic amphipathic structure of antimicrobial peptides (AMPs). Among these amphiphiles, ADG-2e and ADL-3e displayed the highest selectivity against bacterial cells. In this study, ADG-2e and ADL-3e were evaluated for their potential as novel classes of antimicrobial, antibiofilm, and anti-inflammatory agents. METHODS: Minimum inhibitory concentrations of ADG-2e and ADL-3e against bacteria were determined using the broth microdilution method. Proteolytic resistance against pepsin, trypsin, α-chymotrypsin, and proteinase K was determined by radial diffusion and HPLC analysis. Biofilm activity was investigated using the broth microdilution and confocal microscopy. The antimicrobial mechanism was investigated by membrane depolarization, cell membrane integrity analysis, scanning electron microscopy (SEM), genomic DNA influence and genomic DNA binding assay. Synergistic activity was evaluated using checkerboard method. Anti-inflammatory activity was investigated using ELISA and RT-PCR. RESULTS: ADG-2e and ADL-3e showed good resistance to physiological salts and human serum, and a low incidence of drug resistance. Moreover, they exhibit proteolytic resistance against pepsin, trypsin, α-chymotrypsin, and proteinase K. ADG-2e and ADL-3e were found to kill bacteria by an intracellular target mechanism and bacterial cell membrane-disrupting mechanism, respectively. Furthermore, ADG-2e and ADL-3e showed effective synergistic effects when combined with several conventional antibiotics against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Importantly, ADG-2e and ADL-3e not only suppressed MDRPA biofilm formation but also effectively eradicated mature MDRPA biofilms. Furthermore, ADG-2e and ADL-3e drastically decreased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) gene expression and protein secretion in lipopolysaccharide (LPS)-stimulated macrophages, implying potent anti-inflammatory activity in LPS-induced inflammation. CONCLUSION: Our findings suggest that ADG-2e and ADL-3e could be further developed as novel antimicrobial, antibiofilm, and anti-inflammatory agents to combat bacterial infections.
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Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Humanos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Lipopolissacarídeos , Endopeptidase K/farmacologia , Pepsina A/farmacologia , Tripsina/farmacologia , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Inflamatórios/farmacologia , Bactérias , Biofilmes , Timidina/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Malignant Triton tumor (MTT) is a rare variant of malignant peripheral nerve sheath tumor which harbingers a poor prognosis owing to its aggressive behavior. We report a case of a gentleman, who presented with MTT of the lower alveolus, and management with extensive extirpative surgery and adjuvant radiotherapy.
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Hybridizing two known antimicrobial peptides (AMPs) is a simple and effective strategy for designing antimicrobial agents with enhanced cell selectivity against bacterial cells. Here, we generated a hybrid peptide Lf-KR in which LfcinB6 and KR-12-a4 were linked with a Pro hinge to obtain a novel AMP with potent antimicrobial, anti-inflammatory, and anti-biofilm activities. Lf-KR exerted superior cell selectivity for bacterial cells over sheep red blood cells. Lf-KR showed broad-spectrum antimicrobial activities (MIC: 4-8 µM) against tested 12 bacterial strains and retained its antimicrobial activity in the presence of salts at physiological concentrations. Membrane depolarization and dye leakage assays showed that the enhanced antimicrobial activity of Lf-KR was due to increased permeabilization and depolarization of microbial membranes. Lf-KR significantly inhibited the expression and production of pro-inflammatory cytokines (nitric oxide and tumor necrosis factor-α) in LPS-stimulated mouse macrophage RAW264.7 cells. In addition, Lf-KR showed a powerful eradication effect on preformed multidrug-resistant Pseudomonas aeruginosa (MDRPA) biofilms. We confirmed using confocal laser scanning microscopy that a large portion of the preformed MDRPA biofilm structure was perturbed by the addition of Lf-KR. Collectively, our results suggest that Lf-KR can be an antimicrobial, anti-inflammatory, and anti-biofilm candidate as a pharmaceutical agent.
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Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes , Camundongos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , OvinosRESUMO
The concentration of 23 metals was analyzed in the tissue of nine fish species, which represents the different habitats, i.e., primary feeder, tertiary feeder, and bottom feeder in fresh and marine waters of Visakhapatnam. Scomberomorus guttatus, Upeneus vittatus, and Penaeus indicus were selected in the coastal waters; Xiphias gladius, Stolephorus indicus, and Penaeus monodon from deep sea; and Channa striata, Puntius chola, and Macrobrachium rosenbergii from freshwater were analyzed. Metals in fish were analyzed by using the Inductive Couple Plasma Mass Spectrometer (ICP-MS). The concentrations of metals in fish were within the permissible limit set by WHO, FAO apart from Chromium, Aluminum, Manganese, and Arsenic. The concentrations were highest in coastal water fish and lowest in freshwater fish. Similarly, higher concentrations were observed in bottom feeders than in other tiers.
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Metais Pesados , Poluentes Químicos da Água , Animais , Bioacumulação , Ecossistema , Biomarcadores Ambientais , Monitoramento Ambiental , Peixes , Índia , Metais Pesados/análise , Poluentes Químicos da Água/análiseRESUMO
Antimicrobial peptides (AMPs) have gained increasing attention to combat antibiotic-resistant pathogens. dCATH (duck cathelicidin) is a 20-residue avian cathelicidin with potent bactericidal activity. However, its therapeutic application is limited due to high mammalian cell cytotoxicity. To develop therapeutically useful AMPs with enhanced antimicrobial and cell-selective property, we designed a series of 12-meric (dodeca) short amphiphilic peptides based on dCATH. Among these, Trp and Lys-rich dCATH 12-4 and dCATH 12-5 exhibited higher selectivity towards bacterial cells than erythrocytes and macrophages. Additionally, these AMPs significantly reduced NO and TNF-α secretion in LPS-stimulated macrophage cells, suggesting their anti-inflammatory properties. Various fluorophore-based studies and confocal microscopic observations demonstrated that dCATH 12-4 and dCATH 12-5 could penetrate the bacterial cell membrane and accumulate in the cytoplasm, without disrupting membrane integrity. Results from the microscopic examination and gel-retardation DNA binding assay suggested that both the designed AMPs could bind with bacterial DNA, subsequently leading to cell death via arrest of DNA synthesis. Fluorescence spectroscopy and flow cytometry analysis revealed that the designed AMPs induced strong binding to LPS oligomers which resulted in dissociation of LPS aggregates, thereby preventing LPS from binding to the carrier protein lipopolysaccharide-binding protein (LBP) or alternatively to CD14 receptors of macrophage cells. Additionally, both dCATH 12-4 and dCATH 12-5 demonstrated synergistic actions with various conventional antibiotics against antibiotic resistant pathogens, thus indicating their ability as promising adjuncts to combination therapy. In summary, these findings contribute to the design of short AMPs with bactericidal and immunomodulatory properties for combating bacterial infection and sepsis.
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Peptídeos Catiônicos Antimicrobianos/química , Endotoxinas/antagonistas & inibidores , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Patos , Camundongos , Células RAW 264.7 , CatelicidinasRESUMO
The modulation of conformational flexibility in antimicrobial peptides (AMPs) has been investigated as a strategy to improve their efficacy against bacterial pathogens while reducing their toxicity. Here, we synthesized a library of helicity-modulated antimicrobial peptoids by the position-specific incorporation of helix-inducing monomers. The peptoids displayed minimal variations in hydrophobicity, which permitted the specific assessment of the effect of conformational differences on antimicrobial activity and selectivity. Among the moderately helical peptoids, the most dramatic increase in selectivity was observed in peptoid 17, providing more than a 20-fold increase compared to fully helical peptoid 1. Peptoid 17 had potent broad-spectrum antimicrobial activity that included clinically isolated multi-drug-resistant pathogens. Compared to pexiganan AMP, 17 showed superior metabolic stability, which could potentially reduce the dosage needed, alleviating toxicity. Dye-uptake assays and high-resolution imaging revealed that the antimicrobial activity of 17 was, as with many AMPs, mainly due to membrane disruption. However, the high selectivity of 17 reflected its unique conformational characteristics, with differential interactions between bacterial and erythrocyte membranes. Our results suggest a way to distinguish different membrane compositions solely by helicity modulation, thereby improving the selectivity toward bacterial cells with the maintenance of potent and broad-spectrum activity.
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Anti-Infecciosos , Peptoides , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Interações Hidrofóbicas e Hidrofílicas , Peptoides/farmacologiaRESUMO
Maternal diabetes develops in 2-6% of total pregnancies, depending on geographical and ethnic background. About 10% of fetuses from diabetic pregnancy display congenital malformations in various organ systems including cardiovascular, gastrointestinal, genitourinary and neurological systems, among which the neural tube defects (NTDs) such as anencephaly, holoprosencephaly and syntelencephaly were more frequently demonstrated. Recent studies by the Diabetes Control and Complications Trial Research Group show that tight glycemic control early in pregnancy decreases the progression of a number of diabetic complications. However, it appears that the pre-existing tissue damage cannot be reversed even after normoglycemic levels are achieved during pregnancy. In recent years, considerable efforts have been made to investigate the etiology of birth defects among infants of diabetic mothers. It has been shown that diabetes-induced fetal abnormalities are accompanied by some metabolic disturbances including elevated superoxide dismutase (SOD) activity, reduced levels of myoinositol and arachidonic acid and inhibition of the pentose phosphate shunt pathway. Moreover, the frequency of fetal malformations in diabetic pregnancy has been reported to be markedly reduced by dietary supplements of antioxidants such as vitamin E, vitamin C and butylated hy- droxytoluene, suggesting that oxidative stress is involved in the etiology of fetal dysmorphogenesis. Furthermore, several experimental studies have shown that NTDs in embryos of diabetic mice are associated with altered expression of genes, which control development of the neural tube. In this review, recent findings of possible molecular mechanisms which cause morphological changes during neural tube development in embryos of diabetic pregnancy are discussed.
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Diabetes Gestacional/metabolismo , Defeitos do Tubo Neural/etiologia , Gravidez em Diabéticas/metabolismo , Animais , Apoptose , Encéfalo/embriologia , Encéfalo/metabolismo , Encéfalo/patologia , Diabetes Gestacional/epidemiologia , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Tubo Neural/embriologia , Tubo Neural/metabolismo , Tubo Neural/patologia , Defeitos do Tubo Neural/embriologia , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/genética , Estresse Oxidativo , Gravidez , Gravidez em Diabéticas/epidemiologiaRESUMO
Fowlicidin-1 (Fowl-1), a cathelicidin expressed in chicken intestine, is known to have both antimicrobial and anti-inflammatory properties. However, its pharmaceutical development has been ultimately compromised by its high host cytotoxicity. In this study, a series of N- and C-terminal-truncated 19-meric Fowl-1 peptides were synthesized. Among these truncated peptides, Fowl-1 (8-26) exhibited broad-spectrum antimicrobial activity without human erythrocyte cytotoxicity while reducing anti-inflammatory activity. Further, Fowl-1 (8-26)-WRK was designed via Thr5âTrp, Ile7âArg, and Asn11âLys substitutions in Fowl-1 (8-26) to exhibit more amphipathicity. The results revealed that it exhibited both antimicrobial and anti-inflammatory properties. This study also demonstrated that the inhibitory activity of Fowl-1 (8-26)-WRK against LPS-induced inflammation was mainly due to the binding of LPS to the peptide. Interestingly, compared with human cathelicidin LL-37 and melittin, Fowl-1 (8-26)-WRK showed more potent activity against drug-resistant bacteria. It was also resistant to physiological salts and human serum and acted synergistically in combination with conventional antibiotics, such as chloramphenicol, ciprofloxacin, and oxacillin, suggesting that combined with conventional antibiotics, it is a promising adjuvant. Furthermore, membrane depolarization, SYTOX Green uptake, and flow cytometry revealed that it kills bacteria by damaging their membrane integrity. Therefore, this study suggests that Fowl-1 (8-26)-WRK has considerable potential for future development as an antimicrobial and anti-inflammatory agent for treating antibiotic-resistant infections.
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Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Catelicidinas/farmacologia , Desenho de Fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Catelicidinas/síntese química , Catelicidinas/química , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Células RAW 264.7 , Ovinos , Relação Estrutura-AtividadeRESUMO
Maternal diabetes causes congenital malformations in various organs including the neural tube in fetuses. In this study, we have analyzed the differential gene expression profiling in the cranial neural tube of embryos from diabetic and control mice by using the oligonucleotide microarray. Expression patterns of genes and proteins that are differentially expressed in the cranial neural tube were further examined by the real-time reverse transcriptase-polymerase chain reaction, in situ hybridization, and immunohistochemistry. Proliferation index and apoptosis were examined by BrdU (5-bromo-2-deoxyuridine) labeling and TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) assay, respectively. Embryos (E11.5) of diabetic pregnancies displayed distortion in neuroepithelia of the cranial neural tube. Microarray analysis revealed that a total of 390 genes exhibited more than twofold changes in expression level in the cranial neural tube of embryos from diabetic mice. Several genes involving apoptosis, proliferation, migration, and differentiation of neurons in the cranial neural tube were differentially expressed in embryos of diabetic pregnancy. In addition, maternal diabetes perturbed the development of choroid plexus and ventricular systems and reduced the production of proteins such as Ttr and Igf2 in the developing brain, indicating that these changes could impair the survival and proliferation of neuroepithelial cells and neurogenesis in embryos of diabetic mice. It is concluded that altered expression of a variety of genes involved in brain development is associated with cranial neural tube dysmorphogenesis that may subsequently contribute to intellectual impairment of the offspring of a diabetic mother.
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Encéfalo/anormalidades , Complicações do Diabetes/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Defeitos do Tubo Neural/genética , Tubo Neural/anormalidades , Animais , Apoptose/genética , Padronização Corporal/genética , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células , Ventrículos Cerebrais/anormalidades , Ventrículos Cerebrais/patologia , Ventrículos Cerebrais/fisiopatologia , Complicações do Diabetes/metabolismo , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Experimental/complicações , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Tubo Neural/metabolismo , Tubo Neural/fisiopatologia , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/fisiopatologia , Neurônios/metabolismo , Gravidez , Células-Tronco/metabolismoAssuntos
Algoritmos , Pavilhão Auricular/lesões , Deformidades Adquiridas da Orelha/etiologia , Deformidades Adquiridas da Orelha/cirurgia , Procedimentos de Cirurgia Plástica , Adulto , Estudos de Coortes , Árvores de Decisões , Deformidades Adquiridas da Orelha/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retalhos Cirúrgicos , Resultado do Tratamento , Adulto JovemRESUMO
Here we describe the three-dimensional structure and antimicrobial mechanism of mBjAMP1, an antimicrobial peptide (AMP) isolated from Branchiostoma japonicum. The structure of mBjAMP1 was determined by 2D solution NMR spectroscopy and revealed a novel α-hairpinin-like scaffold stabilized by an intramolecular disulfide bond. mBjAMP1 showed effective growth inhibition and bactericidal activities against pathogenic bacteria but was not cytotoxic to mammalian cells. Antimicrobial mechanism studies using fluorescence-based experiments demonstrated that mBjAMP1 did not disrupt membrane integrity. Laser-scanning confocal microscopy indicated that mBjAMP1 is able to penetrate the bacterial cell membrane without causing membrane disruption. Moreover, gel retardation assay suggested that mBjAMP1 directly binds to bacterial DNA as an intracellular target. Collectively, mBjAMP1 may inhibit biological functions by binding to DNA or RNA after penetrating the bacterial cell membrane, thereby causing cell death. These results suggest that mBjAMP1 may present a promising template for the development of peptide-based antibiotics.